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  Discussion on Spaying - risks? Experiences?
Author Message
Member:
Meggles

Posted on Saturday, Aug 13, 2005 - 6:38 am:

Dr O.
I've read the article on spaying mares and some of the members posts. I've reached the end of the line with my mare on regumate, and have now got her on Progesterone injections, plus a small supplement of regumate (she's the horse with epilepsy linked to her seasons). Its costing me a small fortune as animal medications are extortionate here and the side effects, which are unpleasant, don't go away. She no longer has siezures due to being on these drugs and as a result I'm seriously considering having her spayed as without the hormones its likely that the siezures won't return.

It seems that here in the UK the attitude towards spaying mares is different to that in the US, where it seems to be considered less of a big deal (correct me if I'm wrong on this).

My vet is loathe to recommend spaying as its very uncommon here and he is unable to advise me of the nature of the opereration or the risks, both immediate and long term. without going away and seeking advice.

What I have been told is that as its an abdominal surgery there is an increased immediate and long term risk of certain types of colic.

Could you let me have more idea of the procedure that my horse would go through, the recovery period and any risks you are aware of?

If any other members have direct experience of this with their mares I'd be really pleased to hear them, good or bad, to help me make a decision.
Thanks.
Moderator:
DrO

Posted on Saturday, Aug 13, 2005 - 4:30 pm:

Though we don't see it much here Sarah, a vet who gave a lecture on the procedure in the mid-west US said the procedure had become quite routine there and did not describe a increased incidence of colic. The article describes the procedure fairly well and I found this review (below) that in 23 surgeries colic is not described as a complication up 5 and 1/2 years post surgery:

J Am Vet Med Assoc. 1993 Oct 1;203(7):1043-6.
Effects of bilateral ovariectomy via colpotomy in mares: 23 cases (1984-1990).
Hooper RN, Taylor TS, Varner DD, Blanchard TL.
Department of Large Animal Medicine and Surgery, Texas Veterinary Medical Center, Texas A&M University, College Station 77843-4475.

Postoperative performance and behavioral patterns were investigated retrospectively in 23 client-owned mares after bilateral ovariectomy via colpotomy. The interval from surgery to postoperative inquiries ranged from 9 to 67 months. Information obtained from review of the medical record and client interviews included the reason for ovariectomy, postoperative complications, problems identified by owners after discharge of the mare from the hospital, postoperative level of athletic performance, postoperative signs of estrus, and overall owner satisfaction. Reasons given by owners for having mares ovariectomized were behavioral modification (16 mares), use as embryo-transfer recipients (3 mares), use as mount mares for collecting semen (2 mares), elimination of chronic colic during estrus (1 mare), and sterilization for registration (1 mare). Postoperative complications developed in 4% (1/23) of the mares; however, problems were noticed by the owners of 4 other mares after discharge from the hospital. Continuing signs of behavioral estrus were detected in 35% (8/23) of the mares, but in only in 9% (2/23) was the behavior judged to be objectionable by the owner. Of 12 mares used in performance events prior to bilateral ovariectomy, 10 were judged to be competing at greater than preoperative levels, 1 was judged to be competing at the same level, and 1 was judged to be competing at less than preoperative level of performance. Of 18 owners, 14 were satisfied, 2 were undecided, and 2 were dissatisfied with their mare after it had had bilateral ovariectomy.

DrO
Member:
Meggles

Posted on Sunday, Aug 14, 2005 - 7:35 am:

Thanks for this, thats really helpful.

Its interesting that as many as 8 out of 23 mares continue to show signs of behavioural estrus. I understood from my research that mares continue to have flat levels of hormone presence, but that you no longer get the peaks and troughs that cause estrus. Surely though, behavioural estrus would be caused by a peak? That would be enough to cause a seizure in my mare, which is obviously a concern.

When the article says the ovaries are removed by 'colpotomy', what does that mean?

Also, it describes how post operative complications were seen in some mares. What might post operative complications be for that sort of op, if not colic?
Thanks
Moderator:
DrO

Posted on Sunday, Aug 14, 2005 - 6:25 pm:

Though rising levels of estrogen are present during estrus, it occurs in large part because the suppressing effects of progesterone are gone, for more on this see Equine Reproduction » Horse Breeding & Artificial Insemination » Breeding Patterns in Mares and Stallions.

Colpotomy is the ovarectomy procedure described in the article on heat suppression. There are many possibilities for post-op complications including problems that occur following surgery but not related to the surgery but how about vaginal discharge? The whole article should be in my library in my office and I will see if they explain in greater detail tomorrow.
DrO

DrO
Member:
Warwick

Posted on Monday, Aug 15, 2005 - 1:01 pm:

Hi Sarah

Several years ago, I owned a warmblood mare who was spayed at age 6. She had a very complicated history of recurrent colics from the time she was 4 and was spayed during a colic surgery (believe it or not, her 4th surgery) as her ovaries were found upon visual inspection to be heavily diseased. This cured her recurrent colics and today she is a 14 year old mare enjoying a normal life.

Prior to her surgery, this mare was impossible to work during her heat cycles. Even handling her was a real danger and she displayed obvious signs of pain. Regumate had no effect. She now still "cycles" regularly (as your research indicated, she is one of the 8 out of 23 mares), however she works normally and remains calm.

I also have a friend who had her QH mare spayed about 18 years ago when it was a very uncommon procedure in these parts. She was displaying similar behaviour to your mare. Unlike my mare's surgery, I wasn't able to witness the procedure but I believe her surgery was done through the flank. The mare recovered well and lived to a ripe old age.

Neither one of these mares experienced complications from their respective surgeries. The surgeries were done by 2 different clinics. One by a now long retired general practice vet (in my friend's mare's case) and the other by 2 board certified equine surgeons (my mare's case).

Hope this info is of help.

Sue
Member:
Meggles

Posted on Monday, Aug 15, 2005 - 2:58 pm:

Thanks Sue, that is reassuring to know and its great that your mare has benefited so greatly.

Dr O. If my mare was spayed but continued to cycle mildly, as Sue's horse did, and experienced siezures as a result, would it be possible that much smaller doses of regumate could be used at that time to fully prevent the cycling? I'm interested as if I send her for the op, with all of the uncertainty, it would be great to know I can still fall back on the regumate to prevent the siezures if they still occur afterwards as a result of continued cycling. As you know, it is the sheer levels of hormone that I am giving at the moment that is causing me concern. Presumably the effects of adminstering progesterone would be the same, estrogen or no estrogen. Wouldn't they?
Sarah
Moderator:
DrO

Posted on Tuesday, Aug 16, 2005 - 6:18 am:

Yes the progesterone acts on the mind to remove signs of behavioral estrus and certainly will work after surgery. As to whether you will be able to get by with less I am uncertain.
DrO
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